Abstract
By the aid of a goniometer with the optic of a microscope it is possible to measure well reproducible the principal angle of incidence of a polished ore section. It may be used as a standard material constant for identifications. By the use of objective methods, with the aid of photomultiplier tubes and analysis by computation an accuracy of some few minutes of arc is within reach. Whereby certainly the quality of the sections and the polishing have to satisfy high requirements. The measurements are done without using a standard of comparison. They may be used as complement to the common measurements by vertical illumination. Details of the object are measurable down to a minimum diameter of about 15 μm.
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Buchta, P., Schumann, H. Die Messung des Winkels der Minimal-Intensität der Reflexion in der Auflichtmikroskopie von opaken Substanzen, insbesondere von Erzmineralen. Contr. Mineral. and Petrol. 34, 201–210 (1972). https://doi.org/10.1007/BF00373292
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DOI: https://doi.org/10.1007/BF00373292